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[Events]
Format: Layer, Start, End, Style, Name, MarginL, MarginR, MarginV, Effect, Text
Dialogue: 0,0:00:00.67,0:00:03.60,Default,,0000,0000,0000,,This is Pleurobot.
Dialogue: 0,0:00:03.60,0:00:07.13,Default,,0000,0000,0000,,Pleurobot is a robot that we designed\Nto closely mimic a salamander species
Dialogue: 0,0:00:07.13,0:00:09.12,Default,,0000,0000,0000,,called ??
Dialogue: 0,0:00:09.12,0:00:11.49,Default,,0000,0000,0000,,Pleurobot can walk, as you can see here,
Dialogue: 0,0:00:11.49,0:00:14.30,Default,,0000,0000,0000,,and as you'll see later, it can also swim.
Dialogue: 0,0:00:14.30,0:00:16.95,Default,,0000,0000,0000,,So you might ask,\Nwhy did we design this robot?
Dialogue: 0,0:00:16.95,0:00:21.64,Default,,0000,0000,0000,,And in fact, this robot has been designed\Nas a scientific tool for neuroscience.
Dialogue: 0,0:00:21.64,0:00:24.10,Default,,0000,0000,0000,,Indeed, we designed it\Ntogether with neurobiologists
Dialogue: 0,0:00:24.10,0:00:25.98,Default,,0000,0000,0000,,to understand how animals move,
Dialogue: 0,0:00:25.98,0:00:29.53,Default,,0000,0000,0000,,and especially how the spinal cord\Ncontrols locomotion.
Dialogue: 0,0:00:29.53,0:00:31.74,Default,,0000,0000,0000,,But the more I work in biorobotics,
Dialogue: 0,0:00:31.74,0:00:34.18,Default,,0000,0000,0000,,the more I'm really impressed\Nby animal locomotion.
Dialogue: 0,0:00:34.18,0:00:38.45,Default,,0000,0000,0000,,If you think of a dolphin swimming\Nor a cat running or jumping around,
Dialogue: 0,0:00:38.45,0:00:40.49,Default,,0000,0000,0000,,or even us as humans,
Dialogue: 0,0:00:40.49,0:00:41.98,Default,,0000,0000,0000,,when you go jogging or play tennis,
Dialogue: 0,0:00:41.98,0:00:44.09,Default,,0000,0000,0000,,we do amazing things.
Dialogue: 0,0:00:44.09,0:00:47.81,Default,,0000,0000,0000,,And in fact, our nervous system solves\Na very, very complex control problem.
Dialogue: 0,0:00:47.81,0:00:51.12,Default,,0000,0000,0000,,It has to coordinate more\Nor less 200 muscles perfectly,
Dialogue: 0,0:00:51.37,0:00:55.81,Default,,0000,0000,0000,,because if the coordination is bad,\Nwe fall over or we do bad locomotion.
Dialogue: 0,0:00:55.81,0:00:59.45,Default,,0000,0000,0000,,And my goal is to understand\Nhow this works.
Dialogue: 0,0:00:59.45,0:01:02.70,Default,,0000,0000,0000,,There are four main components\Nbehind animal locomotion.
Dialogue: 0,0:01:02.70,0:01:04.96,Default,,0000,0000,0000,,The first component is just the body,
Dialogue: 0,0:01:04.96,0:01:08.49,Default,,0000,0000,0000,,and in fact we should never underestimate\Nwhat extent the biomechanics
Dialogue: 0,0:01:08.49,0:01:10.90,Default,,0000,0000,0000,,already simplify locomotion in animals.
Dialogue: 0,0:01:10.90,0:01:12.48,Default,,0000,0000,0000,,Then you have the spinal cord,
Dialogue: 0,0:01:12.48,0:01:14.52,Default,,0000,0000,0000,,and in the spinal cord you find reflexes,
Dialogue: 0,0:01:14.52,0:01:18.03,Default,,0000,0000,0000,,like multiple reflexes that create\Na sensory motor coordination loop
Dialogue: 0,0:01:18.03,0:01:22.16,Default,,0000,0000,0000,,between neural activity in the spinal cord\Nand mechanical activity.
Dialogue: 0,0:01:22.16,0:01:24.92,Default,,0000,0000,0000,,A third component\Nare central pattern generators.
Dialogue: 0,0:01:24.92,0:01:29.01,Default,,0000,0000,0000,,These are very interesting circuits\Nin the spinal cord of vertebrate animals
Dialogue: 0,0:01:29.01,0:01:33.40,Default,,0000,0000,0000,,that can generate, by themselves, very\Ncoordinated rhythmic patterns of activity
Dialogue: 0,0:01:33.40,0:01:35.98,Default,,0000,0000,0000,,while receiving only\Nvery simple input signals.
Dialogue: 0,0:01:35.98,0:01:38.60,Default,,0000,0000,0000,,And these input signals come from\Ndescending modulation
Dialogue: 0,0:01:38.60,0:01:41.43,Default,,0000,0000,0000,,from higher parts of the brain,\Nfrom the motor cortex, the cerebellum,
Dialogue: 0,0:01:41.43,0:01:45.20,Default,,0000,0000,0000,,the basal ganglia, will all modulate\Nactivity of the spinal cord
Dialogue: 0,0:01:45.20,0:01:46.66,Default,,0000,0000,0000,,while we do locomotion.
Dialogue: 0,0:01:46.66,0:01:49.65,Default,,0000,0000,0000,,But what's interesting is to what extent\Njust a low level component,
Dialogue: 0,0:01:49.65,0:01:52.29,Default,,0000,0000,0000,,the spinal cord, together with the body,\Nalready solves a big part
Dialogue: 0,0:01:52.29,0:01:53.63,Default,,0000,0000,0000,,of the locomotion problem,
Dialogue: 0,0:01:53.63,0:01:57.22,Default,,0000,0000,0000,,and you probably know it by the fact\Nthat you can cut the head of the chicken,
Dialogue: 0,0:01:57.22,0:01:58.66,Default,,0000,0000,0000,,it can still run for a while,
Dialogue: 0,0:01:58.66,0:02:00.96,Default,,0000,0000,0000,,showing that just the lower part,\Nspinal cord and body,
Dialogue: 0,0:02:00.96,0:02:03.49,Default,,0000,0000,0000,,already solves a big part of locomotion.
Dialogue: 0,0:02:03.49,0:02:06.12,Default,,0000,0000,0000,,Now, understanding how this works\Nis very complex,
Dialogue: 0,0:02:06.12,0:02:07.42,Default,,0000,0000,0000,,because first of all,
Dialogue: 0,0:02:07.42,0:02:09.83,Default,,0000,0000,0000,,recording activity in the spinal cord\Nis very difficult.
Dialogue: 0,0:02:09.83,0:02:12.71,Default,,0000,0000,0000,,It's much easier to implant electrodes\Nin the motor cortex
Dialogue: 0,0:02:12.71,0:02:15.66,Default,,0000,0000,0000,,than in the spinal cord, because\Nit's protected by the vertebrae.
Dialogue: 0,0:02:15.66,0:02:17.54,Default,,0000,0000,0000,,Especially in humans,\Nit's very hard to do.
Dialogue: 0,0:02:17.54,0:02:21.16,Default,,0000,0000,0000,,A second difficulty is that locomotion\Nis really due to a very complex
Dialogue: 0,0:02:21.16,0:02:24.44,Default,,0000,0000,0000,,and very dynamic interaction\Nbetween these four components.
Dialogue: 0,0:02:24.44,0:02:28.01,Default,,0000,0000,0000,,So it's very hard to find out\Nwhat's the role of each over time.
Dialogue: 0,0:02:28.01,0:02:32.66,Default,,0000,0000,0000,,This is where biorobots like Pleurobot\Nand mathematical models
Dialogue: 0,0:02:32.66,0:02:34.56,Default,,0000,0000,0000,,can really help.
Dialogue: 0,0:02:34.56,0:02:36.95,Default,,0000,0000,0000,,So what's biorobotics?
Dialogue: 0,0:02:36.95,0:02:38.99,Default,,0000,0000,0000,,Biorobotics is a very active field\Nof research in robotics
Dialogue: 0,0:02:38.99,0:02:42.80,Default,,0000,0000,0000,,where people want to take inspiration\Nfrom animals to make robots
Dialogue: 0,0:02:42.80,0:02:44.57,Default,,0000,0000,0000,,to go outdoors,
Dialogue: 0,0:02:44.57,0:02:47.35,Default,,0000,0000,0000,,like service robots\Nor search-and-rescue robots
Dialogue: 0,0:02:47.35,0:02:48.88,Default,,0000,0000,0000,,or field robots,
Dialogue: 0,0:02:48.88,0:02:51.14,Default,,0000,0000,0000,,and the big goal here is\Nto take inspiration from animals
Dialogue: 0,0:02:51.14,0:02:53.48,Default,,0000,0000,0000,,to make robotics that can handle\Ncomplex terrain --
Dialogue: 0,0:02:53.48,0:02:55.57,Default,,0000,0000,0000,,stairs, mountains, forests,
Dialogue: 0,0:02:55.57,0:02:57.62,Default,,0000,0000,0000,,places where robots\Nstill have difficulties
Dialogue: 0,0:02:57.62,0:02:59.89,Default,,0000,0000,0000,,and where animals can do\Na much better job.
Dialogue: 0,0:02:59.89,0:03:02.47,Default,,0000,0000,0000,,The robot can be\Na wonderful scientific tool as well.
Dialogue: 0,0:03:02.47,0:03:04.58,Default,,0000,0000,0000,,There are some very nice projects\Nwhere robots are used
Dialogue: 0,0:03:04.58,0:03:08.95,Default,,0000,0000,0000,,like a scientific tool for neuroscience,\Nfor biomechanics, or for ?? dynamics.
Dialogue: 0,0:03:08.95,0:03:11.62,Default,,0000,0000,0000,,And this is exactly\Nthe purpose of Pleurobot.
Dialogue: 0,0:03:11.62,0:03:14.47,Default,,0000,0000,0000,,So what we do in my lab\Nis to collaborate with neurobiologists
Dialogue: 0,0:03:14.47,0:03:18.05,Default,,0000,0000,0000,,like Jean-Marie Cabelguen,\Na neurobiologist in Bordeaux in France,
Dialogue: 0,0:03:18.05,0:03:22.34,Default,,0000,0000,0000,,and we want to make spinal cord models\Nand validate them on robots.
Dialogue: 0,0:03:22.34,0:03:23.99,Default,,0000,0000,0000,,And here we want to start simple.
Dialogue: 0,0:03:23.99,0:03:26.04,Default,,0000,0000,0000,,So it's good to start with simple animals
Dialogue: 0,0:03:26.04,0:03:28.40,Default,,0000,0000,0000,,like lampreys, which are\Nvery primitive fish,
Dialogue: 0,0:03:28.40,0:03:30.80,Default,,0000,0000,0000,,and then gradually go toward\Nmore complex locomotion,
Dialogue: 0,0:03:30.80,0:03:32.24,Default,,0000,0000,0000,,like in salamanders,
Dialogue: 0,0:03:32.24,0:03:34.05,Default,,0000,0000,0000,,but also in cats and in humans,
Dialogue: 0,0:03:34.05,0:03:35.72,Default,,0000,0000,0000,,in mammals.
Dialogue: 0,0:03:35.72,0:03:37.88,Default,,0000,0000,0000,,And here, a robot becomes\Nan interesting tool
Dialogue: 0,0:03:37.88,0:03:39.57,Default,,0000,0000,0000,,to validate our models,
Dialogue: 0,0:03:39.57,0:03:42.61,Default,,0000,0000,0000,,and in fact, for me, Pleurobot\Nis a kind of dream becoming true.
Dialogue: 0,0:03:42.61,0:03:46.77,Default,,0000,0000,0000,,Like, more or less 20 years ago\NI was already working on a computer
Dialogue: 0,0:03:46.77,0:03:49.51,Default,,0000,0000,0000,,making simulations of lamprey\Nand salamander locomotion
Dialogue: 0,0:03:49.51,0:03:50.90,Default,,0000,0000,0000,,during my Ph.D.
Dialogue: 0,0:03:50.90,0:03:54.27,Default,,0000,0000,0000,,But I always knew that my simulations\Nwere just approximations.
Dialogue: 0,0:03:54.27,0:03:58.17,Default,,0000,0000,0000,,Like, simulating the physics in water\Nor with mud or with complex ground,
Dialogue: 0,0:03:58.17,0:04:00.89,Default,,0000,0000,0000,,it's very hard to simulate that\Nproperly on a computer.
Dialogue: 0,0:04:00.89,0:04:03.81,Default,,0000,0000,0000,,Why not have a real robot\Nand real physics?
Dialogue: 0,0:04:03.81,0:04:06.83,Default,,0000,0000,0000,,So among all these animals,\None of my favorites is the salamander.
Dialogue: 0,0:04:06.83,0:04:10.22,Default,,0000,0000,0000,,You might as why, and it's because\Nas an amphibian,
Dialogue: 0,0:04:10.22,0:04:12.82,Default,,0000,0000,0000,,it's a really key animal\Nfrom an evolutionary point of view.
Dialogue: 0,0:04:12.82,0:04:14.14,Default,,0000,0000,0000,,It makes a wonderful link
Dialogue: 0,0:04:14.14,0:04:17.02,Default,,0000,0000,0000,,between swimming, as you find it\Nin eels or fish,
Dialogue: 0,0:04:17.02,0:04:21.95,Default,,0000,0000,0000,,and quadruped motion, as you see\Nin mammals, in cats and humans.
Dialogue: 0,0:04:21.95,0:04:23.80,Default,,0000,0000,0000,,And in fact, the modern salamander
Dialogue: 0,0:04:23.80,0:04:25.89,Default,,0000,0000,0000,,is very close to the first\Nterrestrial vertebrate,
Dialogue: 0,0:04:25.89,0:04:27.70,Default,,0000,0000,0000,,so it's almost a living fossil,
Dialogue: 0,0:04:27.70,0:04:30.03,Default,,0000,0000,0000,,which gives us access to our ancestor,
Dialogue: 0,0:04:30.03,0:04:33.26,Default,,0000,0000,0000,,the ancestor to all terrestrial tetrapods.
Dialogue: 0,0:04:33.26,0:04:35.97,Default,,0000,0000,0000,,So the salamander swims by doing\Nwhat's using what's called
Dialogue: 0,0:04:35.97,0:04:37.11,Default,,0000,0000,0000,,a ??? swimming gait,
Dialogue: 0,0:04:37.11,0:04:40.92,Default,,0000,0000,0000,,so they propagate a nice traveling wave\Nof muscle activity from head to tail.
Dialogue: 0,0:04:40.92,0:04:43.15,Default,,0000,0000,0000,,And if you place the salamander\Non the ground,
Dialogue: 0,0:04:43.15,0:04:45.61,Default,,0000,0000,0000,,it switches to what's called\Na walking trot gait.
Dialogue: 0,0:04:45.61,0:04:48.64,Default,,0000,0000,0000,,In this case, you have nice\Nactivation of the limbs
Dialogue: 0,0:04:48.64,0:04:52.05,Default,,0000,0000,0000,,which are very nicely coordinated\Nwith this standing wave undulation
Dialogue: 0,0:04:52.05,0:04:53.47,Default,,0000,0000,0000,,of the body,
Dialogue: 0,0:04:53.47,0:04:57.07,Default,,0000,0000,0000,,and that's exactly the gait\Nthat you are seeing here on Pleurobot.
Dialogue: 0,0:04:57.07,0:04:59.83,Default,,0000,0000,0000,,Now, one thing which is very surprising\Nand fascinating in fact
Dialogue: 0,0:04:59.83,0:05:03.96,Default,,0000,0000,0000,,is the fact that all this can be generated\Njust by the spinal cord and the body.
Dialogue: 0,0:05:03.96,0:05:05.98,Default,,0000,0000,0000,,So if you take ?? salamander --
Dialogue: 0,0:05:05.98,0:05:08.03,Default,,0000,0000,0000,,it's not so nice\Nbut you remove the head --
Dialogue: 0,0:05:08.03,0:05:10.49,Default,,0000,0000,0000,,and if you electrically stimulate\Nthe spinal cord,
Dialogue: 0,0:05:10.49,0:05:13.94,Default,,0000,0000,0000,,at low level of stimulation\Nthis will use a walking-like gait.
Dialogue: 0,0:05:13.94,0:05:16.52,Default,,0000,0000,0000,,If you stimulate a bit more,\Nthe gait accelerates,
Dialogue: 0,0:05:16.52,0:05:19.12,Default,,0000,0000,0000,,and at some point, there's a transfer,\Nand automatically,
Dialogue: 0,0:05:19.12,0:05:21.32,Default,,0000,0000,0000,,the animal switches to swimming.
Dialogue: 0,0:05:21.32,0:05:22.64,Default,,0000,0000,0000,,This is amazing,
Dialogue: 0,0:05:22.64,0:05:25.50,Default,,0000,0000,0000,,just changing the global drive\Nas if you are pressing the gas pedal
Dialogue: 0,0:05:25.50,0:05:27.92,Default,,0000,0000,0000,,of descending modulation\Nto your spinal cord,
Dialogue: 0,0:05:27.92,0:05:32.07,Default,,0000,0000,0000,,makes a complete switch\Nbetween two very different gaits.
Dialogue: 0,0:05:32.07,0:05:35.25,Default,,0000,0000,0000,,And in fact, the same\Nhas been observed in cats.
Dialogue: 0,0:05:35.25,0:05:36.86,Default,,0000,0000,0000,,If you stimulate the spinal cord of a cat,
Dialogue: 0,0:05:36.86,0:05:39.20,Default,,0000,0000,0000,,you can switch between\Nwalk, trot, and gallop.
Dialogue: 0,0:05:39.20,0:05:42.08,Default,,0000,0000,0000,,Or in birds, you can make a bird\Nswitch between walking,
Dialogue: 0,0:05:42.08,0:05:43.54,Default,,0000,0000,0000,,at low levels of stimulation,
Dialogue: 0,0:05:43.54,0:05:46.38,Default,,0000,0000,0000,,and flapping its wings\Nat high level stimulation.
Dialogue: 0,0:05:46.38,0:05:49.42,Default,,0000,0000,0000,,And this really shows that the spinal cord\Nis a very sophisticated
Dialogue: 0,0:05:49.42,0:05:51.09,Default,,0000,0000,0000,,locomotion controller.
Dialogue: 0,0:05:51.09,0:05:53.34,Default,,0000,0000,0000,,So we studied salamander locomotion\Nin more detail,
Dialogue: 0,0:05:53.34,0:05:56.64,Default,,0000,0000,0000,,and we had in fact access\Nto a very nice x-ray video machine
Dialogue: 0,0:05:56.64,0:05:59.94,Default,,0000,0000,0000,,from Professor Martin Fischer\Nin Jena University in Germany.
Dialogue: 0,0:05:59.94,0:06:03.00,Default,,0000,0000,0000,,And thanks to that, you really have\Nan amazing machine
Dialogue: 0,0:06:03.00,0:06:05.44,Default,,0000,0000,0000,,to record all the bone motion\Nin great detail.
Dialogue: 0,0:06:05.44,0:06:06.76,Default,,0000,0000,0000,,That's what we did.
Dialogue: 0,0:06:06.76,0:06:09.87,Default,,0000,0000,0000,,So we basically figured out\Nwhich bones are important for us
Dialogue: 0,0:06:09.87,0:06:12.52,Default,,0000,0000,0000,,and collected their motion in 3D.
Dialogue: 0,0:06:12.52,0:06:15.40,Default,,0000,0000,0000,,And what we did is collect\Na whole database of motions,
Dialogue: 0,0:06:15.40,0:06:17.19,Default,,0000,0000,0000,,both on ground and in water,
Dialogue: 0,0:06:17.19,0:06:19.35,Default,,0000,0000,0000,,to really collect the whole database\Nof motor behaviors
Dialogue: 0,0:06:19.35,0:06:21.04,Default,,0000,0000,0000,,that a real animal can do,
Dialogue: 0,0:06:21.04,0:06:23.64,Default,,0000,0000,0000,,and then our job as roboticists\Nwas to replicate that in our robot.
Dialogue: 0,0:06:23.64,0:06:27.45,Default,,0000,0000,0000,,So we did a whole optimization process\Nto find out the right structure,
Dialogue: 0,0:06:27.45,0:06:30.12,Default,,0000,0000,0000,,where to place the motors,\Nhow to connect them together,
Dialogue: 0,0:06:30.12,0:06:33.69,Default,,0000,0000,0000,,to be able to replay\Nthese motions as well as possible.
Dialogue: 0,0:06:33.69,0:06:36.02,Default,,0000,0000,0000,,And this is how Pleurobot came to life.
Dialogue: 0,0:06:37.18,0:06:40.06,Default,,0000,0000,0000,,So let's look how closely it is\Nto the real animal.
Dialogue: 0,0:06:40.06,0:06:43.52,Default,,0000,0000,0000,,So what you see here is almost\Na direct comparison
Dialogue: 0,0:06:43.52,0:06:46.24,Default,,0000,0000,0000,,between the walking\Nof the real animal and the Pleurobot.
Dialogue: 0,0:06:46.24,0:06:48.89,Default,,0000,0000,0000,,You can see that we have almost\NA one-to-one exact replay
Dialogue: 0,0:06:48.89,0:06:50.51,Default,,0000,0000,0000,,of the walking gait.
Dialogue: 0,0:06:50.51,0:06:53.34,Default,,0000,0000,0000,,If you go backwards and slowly,\Nyou see it even better.
Dialogue: 0,0:06:55.78,0:06:58.15,Default,,0000,0000,0000,,But even better, we can do swimming.
Dialogue: 0,0:06:58.15,0:07:00.68,Default,,0000,0000,0000,,So for that we have a dry suit\Nthat we put all over the robot --
Dialogue: 0,0:07:00.68,0:07:02.26,Default,,0000,0000,0000,,(Laughter) --
Dialogue: 0,0:07:02.26,0:07:05.46,Default,,0000,0000,0000,,and then we can go in water\Nand start replaying the swimming gaits.
Dialogue: 0,0:07:05.46,0:07:07.58,Default,,0000,0000,0000,,And here, we were very happy,\Nbecause this is difficult to do.
Dialogue: 0,0:07:07.58,0:07:10.78,Default,,0000,0000,0000,,The physics of interaction are complex.
Dialogue: 0,0:07:10.78,0:07:13.31,Default,,0000,0000,0000,,Our robot is much bigger\Nthan a small animal,
Dialogue: 0,0:07:13.31,0:07:16.10,Default,,0000,0000,0000,,so we had to do what's called\Ndynamical scaling of the frequencies
Dialogue: 0,0:07:16.10,0:07:18.63,Default,,0000,0000,0000,,to make sure we had the same\Ninteraction physics.
Dialogue: 0,0:07:18.63,0:07:21.30,Default,,0000,0000,0000,,But you see at the end\Nwe have a very close match,
Dialogue: 0,0:07:21.30,0:07:23.72,Default,,0000,0000,0000,,and we were very, very happy with this.
Dialogue: 0,0:07:23.72,0:07:25.85,Default,,0000,0000,0000,,So let's go do the spinal cord.
Dialogue: 0,0:07:25.85,0:07:27.99,Default,,0000,0000,0000,,So here what we did\Nwith Jean-Marie Cabelguen
Dialogue: 0,0:07:27.99,0:07:30.47,Default,,0000,0000,0000,,is model the spinal cord circuits.
Dialogue: 0,0:07:30.47,0:07:33.40,Default,,0000,0000,0000,,And what's interesting is that\Nthe salamander has kept
Dialogue: 0,0:07:33.40,0:07:34.93,Default,,0000,0000,0000,,a very primitive circuit
Dialogue: 0,0:07:34.93,0:07:37.53,Default,,0000,0000,0000,,which is very similar to the one\Nwe find in the lamprey,
Dialogue: 0,0:07:37.53,0:07:39.50,Default,,0000,0000,0000,,pretty much this eel-like fish,
Dialogue: 0,0:07:39.50,0:07:41.20,Default,,0000,0000,0000,,and it looks like during evolution,
Dialogue: 0,0:07:41.20,0:07:44.50,Default,,0000,0000,0000,,new neuronal oscillators have been added\Nto control the limbs,
Dialogue: 0,0:07:44.50,0:07:46.03,Default,,0000,0000,0000,,to do the leg locomotion.
Dialogue: 0,0:07:46.03,0:07:48.00,Default,,0000,0000,0000,,And we know where\Nthese neuronal oscillators are
Dialogue: 0,0:07:48.00,0:07:49.100,Default,,0000,0000,0000,,but what we did was to make\Na mathematical model
Dialogue: 0,0:07:49.100,0:07:51.51,Default,,0000,0000,0000,,to see how they should be coupled
Dialogue: 0,0:07:51.51,0:07:54.32,Default,,0000,0000,0000,,to allow this transition between\Nthe two very different gaits.
Dialogue: 0,0:07:54.32,0:07:57.94,Default,,0000,0000,0000,,And we tested that on board of a robot.
Dialogue: 0,0:07:57.94,0:07:59.73,Default,,0000,0000,0000,,And this is how it looks.
Dialogue: 0,0:08:06.72,0:08:08.25,Default,,0000,0000,0000,,So what you see here
Dialogue: 0,0:08:08.25,0:08:10.18,Default,,0000,0000,0000,,is a previous version of Pleurobot
Dialogue: 0,0:08:10.18,0:08:12.80,Default,,0000,0000,0000,,that's completely controlled\Nby our spinal cord model
Dialogue: 0,0:08:12.80,0:08:14.89,Default,,0000,0000,0000,,programmed on board of the robot.
Dialogue: 0,0:08:14.89,0:08:17.72,Default,,0000,0000,0000,,And the only thing we do\Nis send to the robot
Dialogue: 0,0:08:17.72,0:08:19.05,Default,,0000,0000,0000,,through a remote control
Dialogue: 0,0:08:19.05,0:08:21.14,Default,,0000,0000,0000,,the two descending signals\Nit normally should receive
Dialogue: 0,0:08:21.14,0:08:23.27,Default,,0000,0000,0000,,from the upper part of the brain.
Dialogue: 0,0:08:23.27,0:08:25.36,Default,,0000,0000,0000,,And what's interesting is,\Nby playing with these signals,
Dialogue: 0,0:08:25.36,0:08:29.80,Default,,0000,0000,0000,,we can completely control\Nspeed, heading, and type of gait.
Dialogue: 0,0:08:29.80,0:08:31.05,Default,,0000,0000,0000,,For instance,
Dialogue: 0,0:08:31.05,0:08:33.100,Default,,0000,0000,0000,,when we stimulate at a low level,\Nwe have the walking gait,
Dialogue: 0,0:08:33.100,0:08:37.36,Default,,0000,0000,0000,,and at some point, if we stimulate a lot,\Nvery rapidly it switches
Dialogue: 0,0:08:37.36,0:08:39.52,Default,,0000,0000,0000,,to the swimming gait.
Dialogue: 0,0:08:39.52,0:08:41.26,Default,,0000,0000,0000,,And finally, we can also do turning
Dialogue: 0,0:08:41.26,0:08:46.12,Default,,0000,0000,0000,,very nicely by just stimulating more one\Nside of the spinal cord than the other.
Dialogue: 0,0:08:46.12,0:08:47.88,Default,,0000,0000,0000,,And I think it's really beautiful
Dialogue: 0,0:08:47.88,0:08:50.20,Default,,0000,0000,0000,,how nature has distributed control
Dialogue: 0,0:08:50.20,0:08:52.82,Default,,0000,0000,0000,,to really give a lot of responsibility\Nto the spinal cord
Dialogue: 0,0:08:52.82,0:08:56.38,Default,,0000,0000,0000,,so that the upper part of the brain\Ndoesn't need to worry about every muscle.
Dialogue: 0,0:08:56.38,0:08:58.75,Default,,0000,0000,0000,,It just has to worry about\Nthis high-level modulation,
Dialogue: 0,0:08:58.75,0:09:03.09,Default,,0000,0000,0000,,and it's really the job of the spinal cord\Nto coordinate all the muscles.
Dialogue: 0,0:09:03.09,0:09:06.94,Default,,0000,0000,0000,,So now let's go to cat locomotion,\Nand the importance of biomechanics.
Dialogue: 0,0:09:06.94,0:09:08.59,Default,,0000,0000,0000,,So this is another project
Dialogue: 0,0:09:08.59,0:09:10.82,Default,,0000,0000,0000,,where we studied cat biomechanics,
Dialogue: 0,0:09:10.82,0:09:14.95,Default,,0000,0000,0000,,and we wanted to see how much\Nthe morphology helps locomotion.
Dialogue: 0,0:09:14.95,0:09:18.62,Default,,0000,0000,0000,,And we found three important\Ncriteria in the properties,
Dialogue: 0,0:09:18.62,0:09:20.29,Default,,0000,0000,0000,,basically, of the limbs.
Dialogue: 0,0:09:20.29,0:09:22.24,Default,,0000,0000,0000,,The first one is that a cat limb
Dialogue: 0,0:09:22.24,0:09:24.84,Default,,0000,0000,0000,,more or less looks\Nlike a pantograph-like structure.
Dialogue: 0,0:09:24.84,0:09:27.25,Default,,0000,0000,0000,,So a pantograph is a mechanical structure
Dialogue: 0,0:09:27.25,0:09:31.73,Default,,0000,0000,0000,,which keeps the upper segment\Nand the lower segments always parallel.
Dialogue: 0,0:09:31.73,0:09:34.45,Default,,0000,0000,0000,,So a simple geometrical system\Nthat kind of coordinates a bit
Dialogue: 0,0:09:34.45,0:09:36.42,Default,,0000,0000,0000,,the internal movement of the segments.
Dialogue: 0,0:09:36.42,0:09:39.37,Default,,0000,0000,0000,,A second property of cat limbs\Nis that they are very lightweight.
Dialogue: 0,0:09:39.37,0:09:41.51,Default,,0000,0000,0000,,Most of the muscles are in the trunk,
Dialogue: 0,0:09:41.51,0:09:44.02,Default,,0000,0000,0000,,which is a good idea, because then\Nthe limbs have low inertia
Dialogue: 0,0:09:44.02,0:09:46.04,Default,,0000,0000,0000,,and can be moved very rapidly.
Dialogue: 0,0:09:46.04,0:09:50.17,Default,,0000,0000,0000,,The last final important property is this\Nvery elastic behavior of the cat limb,
Dialogue: 0,0:09:50.17,0:09:52.77,Default,,0000,0000,0000,,so to handle impacts and forces.
Dialogue: 0,0:09:52.77,0:09:55.02,Default,,0000,0000,0000,,And this is how we designed Cheetah-Cub.
Dialogue: 0,0:09:55.02,0:09:57.37,Default,,0000,0000,0000,,So let's invite Cheetah-Cub onstage.
Dialogue: 0,0:09:57.37,0:10:06.07,Default,,0000,0000,0000,,So this is Peter Eckert, who does\Nhis Ph.D on this robot,
Dialogue: 0,0:10:06.07,0:10:08.14,Default,,0000,0000,0000,,and as you see, it's a cute little robot.
Dialogue: 0,0:10:08.14,0:10:09.28,Default,,0000,0000,0000,,It looks a bit like a toy,
Dialogue: 0,0:10:09.28,0:10:11.37,Default,,0000,0000,0000,,But it was really used\Nas a scientific tool
Dialogue: 0,0:10:11.37,0:10:14.60,Default,,0000,0000,0000,,to investigate these properties\Nof the legs of the cat.
Dialogue: 0,0:10:14.60,0:10:16.78,Default,,0000,0000,0000,,So you see, it's very compliant,\Nvery lightweight,
Dialogue: 0,0:10:16.78,0:10:18.82,Default,,0000,0000,0000,,and also very elastic,
Dialogue: 0,0:10:18.82,0:10:21.30,Default,,0000,0000,0000,,so you can easily press it down\Nand it will not break.
Dialogue: 0,0:10:21.30,0:10:23.07,Default,,0000,0000,0000,,It will just jump, in fact.
Dialogue: 0,0:10:23.07,0:10:26.62,Default,,0000,0000,0000,,And this very elastic property\Nis also very important.
Dialogue: 0,0:10:26.62,0:10:29.83,Default,,0000,0000,0000,,And you also see a bit this properties\Nof these three segments
Dialogue: 0,0:10:29.83,0:10:32.57,Default,,0000,0000,0000,,of the leg as pantograph.
Dialogue: 0,0:10:32.57,0:10:35.17,Default,,0000,0000,0000,,Now, what's interesting is that\Nthis quite dynamic gait
Dialogue: 0,0:10:35.17,0:10:36.96,Default,,0000,0000,0000,,is obtained purely in open loop,
Dialogue: 0,0:10:36.96,0:10:38.32,Default,,0000,0000,0000,,meaning no sensors,\Nno complex feedback loops.
Dialogue: 0,0:10:38.32,0:10:42.46,Default,,0000,0000,0000,,And that's interesting, because it means
Dialogue: 0,0:10:42.46,0:10:46.40,Default,,0000,0000,0000,,that just the mechanics already stabilized\Nthis quite rapid gait,
Dialogue: 0,0:10:46.40,0:10:51.10,Default,,0000,0000,0000,,and that really good mechanics\Nalready basically simplify locomotion.
Dialogue: 0,0:10:51.10,0:10:54.09,Default,,0000,0000,0000,,To the extent that we can even\Ndisturb a bit locomotion,
Dialogue: 0,0:10:54.09,0:10:55.83,Default,,0000,0000,0000,,as you will see in the next video,
Dialogue: 0,0:10:55.83,0:10:59.59,Default,,0000,0000,0000,,where we can for instance do some exercise\Nwhere we have the robot go down a step,
Dialogue: 0,0:10:59.59,0:11:01.47,Default,,0000,0000,0000,,and the robot will not fall over,
Dialogue: 0,0:11:01.47,0:11:03.22,Default,,0000,0000,0000,,which was a surprise for us.
Dialogue: 0,0:11:03.22,0:11:04.56,Default,,0000,0000,0000,,This is a small perturbation.
Dialogue: 0,0:11:04.56,0:11:06.54,Default,,0000,0000,0000,,I was expecting the robot\Nto immediately fall over,
Dialogue: 0,0:11:06.54,0:11:08.81,Default,,0000,0000,0000,,because there is no sensors,\Nno fast feedback loop.
Dialogue: 0,0:11:08.81,0:11:11.20,Default,,0000,0000,0000,,But no, just the mechanics\Nstabilized the gait,
Dialogue: 0,0:11:11.20,0:11:12.85,Default,,0000,0000,0000,,and the robot doesn't fall over.
Dialogue: 0,0:11:12.85,0:11:15.92,Default,,0000,0000,0000,,Obviously, if you make the step bigger,\Nand if you have obstacles,
Dialogue: 0,0:11:15.92,0:11:19.84,Default,,0000,0000,0000,,you need the full control loops\Nand reflexes and everything,
Dialogue: 0,0:11:19.84,0:11:22.46,Default,,0000,0000,0000,,but what's important here\Nis that just for small perturbation,
Dialogue: 0,0:11:22.46,0:11:24.46,Default,,0000,0000,0000,,the mechanics are right.
Dialogue: 0,0:11:24.46,0:11:26.09,Default,,0000,0000,0000,,And I think this is\Na very important message
Dialogue: 0,0:11:26.09,0:11:28.80,Default,,0000,0000,0000,,from biomechanics and robotics\Nto neuroscience,
Dialogue: 0,0:11:28.80,0:11:30.75,Default,,0000,0000,0000,,saying don't underestimate to what extent
Dialogue: 0,0:11:30.75,0:11:34.44,Default,,0000,0000,0000,,the body already helps locomotion.
Dialogue: 0,0:11:34.44,0:11:37.74,Default,,0000,0000,0000,,Now, how does this relate\Nto human locomotion?
Dialogue: 0,0:11:37.74,0:11:42.18,Default,,0000,0000,0000,,Clearly, human locomotion is more complex\Nthan cat and salamander locomotion,
Dialogue: 0,0:11:42.18,0:11:45.17,Default,,0000,0000,0000,,but at the same time, the nervous system\Nof humans is very similar
Dialogue: 0,0:11:45.17,0:11:47.36,Default,,0000,0000,0000,,to that of other vertebrates.
Dialogue: 0,0:11:48.02,0:11:52.04,Default,,0000,0000,0000,,and especially the spinal cord is also the\Nkey controller for locomotion in humans.
Dialogue: 0,0:11:52.04,0:11:53.94,Default,,0000,0000,0000,,That's why, if there's a lesion\Nof the spinal cord,
Dialogue: 0,0:11:53.94,0:11:55.80,Default,,0000,0000,0000,,this has dramatic effects.
Dialogue: 0,0:11:55.80,0:11:57.48,Default,,0000,0000,0000,,The person can become \Nparaplegic or tetraplegic.
Dialogue: 0,0:11:57.48,0:12:00.92,Default,,0000,0000,0000,,This is become the brain\Nloses its communication
Dialogue: 0,0:12:00.92,0:12:02.22,Default,,0000,0000,0000,,with the spinal cord.
Dialogue: 0,0:12:02.22,0:12:04.41,Default,,0000,0000,0000,,Especially, it loses\Nthe descending modulation
Dialogue: 0,0:12:04.41,0:12:07.50,Default,,0000,0000,0000,,to initiate and modulate locomotion.
Dialogue: 0,0:12:07.50,0:12:09.31,Default,,0000,0000,0000,,So a big goal of neuroprosthetics
Dialogue: 0,0:12:09.31,0:12:11.70,Default,,0000,0000,0000,,is to be able to reactivate\Nthat communication
Dialogue: 0,0:12:11.70,0:12:14.67,Default,,0000,0000,0000,,using electrical or chemical stimulations.
Dialogue: 0,0:12:14.67,0:12:17.36,Default,,0000,0000,0000,,And there are several teams\Nin the world that do exactly that,
Dialogue: 0,0:12:17.36,0:12:18.71,Default,,0000,0000,0000,,especially at EPFL.
Dialogue: 0,0:12:18.71,0:12:21.22,Default,,0000,0000,0000,,My colleagues ?? and ??,
Dialogue: 0,0:12:21.22,0:12:23.42,Default,,0000,0000,0000,,with whom I collaborate.
Dialogue: 0,0:12:23.42,0:12:26.74,Default,,0000,0000,0000,,But to do this properly,\Nit's very important to understand
Dialogue: 0,0:12:26.74,0:12:28.65,Default,,0000,0000,0000,,how the spinal cord works,
Dialogue: 0,0:12:28.65,0:12:30.55,Default,,0000,0000,0000,,how it interacts with the body,
Dialogue: 0,0:12:30.55,0:12:34.06,Default,,0000,0000,0000,,and how the brain communicates\Nwith the spinal cord.
Dialogue: 0,0:12:34.06,0:12:36.52,Default,,0000,0000,0000,,This is where the robots\Nand models that I've presented today
Dialogue: 0,0:12:36.52,0:12:38.56,Default,,0000,0000,0000,,will hopefully play a key role
Dialogue: 0,0:12:38.56,0:12:41.30,Default,,0000,0000,0000,,towards these very important goals.
Dialogue: 0,0:12:41.30,0:12:42.76,Default,,0000,0000,0000,,Thank you.
Dialogue: 0,0:12:42.76,0:12:48.83,Default,,0000,0000,0000,,(Applause)
Dialogue: 0,0:12:51.91,0:12:54.30,Default,,0000,0000,0000,,Bruno Giussani: Okay, I've seen\Nin your lab other robots
Dialogue: 0,0:12:54.30,0:12:57.53,Default,,0000,0000,0000,,that do things like swim in pollution\Nand measure the pollution
Dialogue: 0,0:12:57.53,0:12:59.67,Default,,0000,0000,0000,,while they swim,
Dialogue: 0,0:12:59.67,0:13:04.73,Default,,0000,0000,0000,,but for this one, you mentioned\Nin your talk, like a side project,
Dialogue: 0,0:13:04.73,0:13:06.84,Default,,0000,0000,0000,,search and rescue,
Dialogue: 0,0:13:06.84,0:13:09.10,Default,,0000,0000,0000,,and it does have a camera on its nose.
Dialogue: 0,0:13:09.10,0:13:12.85,Default,,0000,0000,0000,,Auke Ijspeert: Absolutely. So the robot,\Nwe have some spinoff projects
Dialogue: 0,0:13:12.85,0:13:16.05,Default,,0000,0000,0000,,where we would like to use the robots\Nto do search and rescue inspection,
Dialogue: 0,0:13:16.05,0:13:17.77,Default,,0000,0000,0000,,so this robot is now seeing you.
Dialogue: 0,0:13:17.77,0:13:21.44,Default,,0000,0000,0000,,And the big dream is to,\Nif you have a difficult situation
Dialogue: 0,0:13:21.44,0:13:24.88,Default,,0000,0000,0000,,like a collapsed building\Nor a building that is flooded,
Dialogue: 0,0:13:24.88,0:13:28.54,Default,,0000,0000,0000,,and this is very dangerous\Nfor a rescue team or even rescue dogs,
Dialogue: 0,0:13:28.54,0:13:31.38,Default,,0000,0000,0000,,why not send in a robot\Nthat can crawl around, swim, walk,
Dialogue: 0,0:13:31.38,0:13:34.74,Default,,0000,0000,0000,,with a camera onboard\Nto do inspection and identify survivors
Dialogue: 0,0:13:34.74,0:13:36.100,Default,,0000,0000,0000,,and possibly create a communication link\Nwith the survivor.
Dialogue: 0,0:13:36.100,0:13:41.25,Default,,0000,0000,0000,,BG: Of course, assuming the survivors\Ndon't get scared by the shape of this.
Dialogue: 0,0:13:41.25,0:13:44.43,Default,,0000,0000,0000,,AI: Yeah, we should probably change\Nthe appearance quite a bit,
Dialogue: 0,0:13:44.43,0:13:47.07,Default,,0000,0000,0000,,because here I guess a survivor\Nmight die of a heart attack
Dialogue: 0,0:13:47.07,0:13:49.74,Default,,0000,0000,0000,,just by being worried that this\Nwould feed on you.
Dialogue: 0,0:13:49.74,0:13:52.46,Default,,0000,0000,0000,,But by changing the appearance\Nand it making it more robust,
Dialogue: 0,0:13:52.46,0:13:53.88,Default,,0000,0000,0000,,I'm sure we can make\Na good tool out of it.
Dialogue: 0,0:13:53.88,0:13:56.22,Default,,0000,0000,0000,,BG: All right, thank you very much.\NThank you and your team.
Dialogue: 0,0:13:56.22,0:13:57.10,Default,,0000,0000,0000,,(Applause)